PURPOSE: To effectively remove lubricative coats including a phosphate coat laminated on the surface of the material of cold pressed parts by successively immersing the cold pressed parts in an alkali degreasing soln., a phosphoric acid-based pickling soln. and a neutralizing soln.

CONSTITUTION: The material of cold pressed parts has a phosphate coat, a zinc stearate coat and a sodium stearate coat successively laminated on the surface. The cold pressed parts are immersed in an alkali degreasing soln. to roughly remove the sodium stearate coat and the parts are washed with hot water. The zinc stearate coat and the phosphate coat are then dissolved and removed by immersion in a phosphoric acid-based pickling soln. and the parts are washed with water and neutralized by immersion in a neutralizing soln. The lubricative coats can easily be removed without scratching the surfaces of the cold pressed parts.